"Cable unplugged" after upgrade

Issues related to configuring your network
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Latenights
Posts: 10
Joined: 2018/01/25 08:51:48

"Cable unplugged" after upgrade

Post by Latenights » 2019/09/26 23:14:04

I just applied upgrades and rebooted. There is no internet connection and the Network Tool says Cable Unplugged. Also the router LED for this cable connection is off. But I rebooted with the previous kernel and all works again.

New kernel says cable is unplugged
kernel-3.10.0-1062.1.1.el7.x86_64

Previous kernel that works OK
kernel-3.10.0-957.12.2.el7.x86_64

# lspci -nn | grep -i net
03:00.0 Network controller [0280]: Ralink corp. RT3090 Wireless 802.11n 1T/1R PCIe [1814:3090]
04:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 03)

Before I upgrade to Centos 8 I need to know what the problem is in case I need to fix it in 8.

chemal
Posts: 742
Joined: 2013/12/08 19:44:49

Re: "Cable unplugged" after upgrade

Post by chemal » 2019/09/27 01:01:11

My [10ec:8168] also hehaved strangely when I updated to 7.7 (from CR). But starting with the next day everything was ok again. Try to cold start your computer. :)

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jlehtone
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Joined: 2007/12/11 08:17:33
Location: Finland

Re: "Cable unplugged" after upgrade

Post by jlehtone » 2019/09/27 07:52:01

Similar with [10ec:8168] (rev 02)

Steps that I took:
1. yum update ; reboot
2. "Cable unplugged"
3. Reboot to previous kernel
4. Remove 3.10.0-1062.1.1
5. Exclude kernel from yum
... some days ...
6. Enable kernel ; reinstall 3.10.0-1062.1.1 ; reboot
7. Still "Cable unplugged"
8. Attempt "ethtool -s autoneg off" (Google: years ago that was a workaround). Result: "Not possible"
9. rmmod r8169 ; modprobe r8169 ; still down
9. Reboot
10. Miraculously the link is up

The r8169 has been updated between 7.6 and 7.7.

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TrevorH
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Re: "Cable unplugged" after upgrade

Post by TrevorH » 2019/09/27 17:49:57

If you see the problem again then try modprobe realtek and then retry. If that doesn't work try removing and reloading r8169 with realtek already loaded.
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Latenights
Posts: 10
Joined: 2018/01/25 08:51:48

Re: "Cable unplugged" after upgrade

Post by Latenights » 2019/09/29 10:38:03

chemal wrote:
2019/09/27 01:01:11
My [10ec:8168] also hehaved strangely when I updated to 7.7 (from CR). But starting with the next day everything was ok again. Try to cold start your computer. :)
Solved! I shutdown, unplugged the power for 20 seconds.
Plugged it back in, rebooted into the latest kernel, networking came up no problems.

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